1. Field of the Invention
The present invention relates to a dustproof device for a linear guide rail, which is used to protect bolt holes formed in a linear guide rail for a linear guide bearing apparatus from foreign matters such as cutting dust or the like.
2. Description of the Related Art
Generally, a linear guide rail for a linear guide bearing apparatus is formed with a plurality of bolt holes for bolting the linear guide rail. In the case where the linear guide rail is installed to, for example, a linear slide portion of a machine tool by using these bolt holes, cutting dust of workpiece or the like intrudes into and accumulates in the bolt hole in the linear guide rail, so that when a slider of the linear guide bearing apparatus moves on the linear guide rail, the cutting dust accumulating in the bolt hole intrudes into the slider, which remarkably decreases a life of the linear guide bearing apparatus. Therefore, in order to prevent such a deficiency, a dustproof device 1 shown in FIG. 16 which protects bolt holes 3 in a linear guide rail 2 from foreign matters such as cutting dust has been disclosed in Japanese Patent Laid-Open No. 8-219152.
The dustproof device 1 shown in FIG. 16 includes a band-like cover body 4 covering a guide rail face 2a including the bolt holes 3 and tension applying means 5 for applying a tension in a lengthwise direction of the linear guide rail 2 to the band-like cover body 4. The band-like cover body 4 is formed of, for example, a hardened stainless steel sheet (thickness: about 0.15 to 0.3 mm).
The tension applying means 5 is provided with a pair of moving pieces 6, and each of the moving piece 6 is connected with one end portion of the band-like cover body 4. Also, the tension applying means 5 is provided with a pair of cover fixing members 8 each fixed to the end face of the linear guide rail 2 by means of a plurality of bolts 7, so that when the moving piece 6 fitted in a hollow portion 8a of the cover fixing member 8 is tightened to both end faces of the linear guide rail 2 by a bolt 9, a tension is applied to the band-like cover body 4.
In the above-described dustproof device 1, since the guide rail face 2a including the bolt holes 3 is covered by the band-like cover body 4, foreign matters such as cutting dust can be prevented from intruding into and accumulating in the bolt holes 3. However, many tap holes (threaded holes) 10 must be formed in an end face of the linear guide rail 2, which presents a problem of troublesome work for forming the tap holes 10.
Also, the configuration is such that the moving piece 6 fitted in the hollow portion 8a of the cover fixing member 8 is pulled toward the end face of the linear guide rail 2 by the tightening force of the bolt 9 to apply a tension to the band-like cover body 4. Therefore, the cover fixing member 8 is relatively long. As a result, there arises a problem in that a length of the whole of the linear guide rail including the dustproof device 1 increases.
Furthermore, there arises a problem in that a space for adjusting the tension of the band-like cover body 4 by operating the bolt 9 is needed on both end sides of the linear guide rail 2.
The present invention has been achieved to solve the above problems, and accordingly an object thereof is to provide a dustproof device for linear guide rail capable of protecting bolt holes in a linear guide rail from foreign matters such as cutting dust or the like without many tap holes formed in the end face of the linear guide rail.
To attain the above object, a first aspect of the present invention provides a dustproof device for linear guide rail, including a band-like cover body covering a guide rail face including bolt holes for bolting a linear guide rail having a concave portion such as a rolling element rolling groove on the side faces thereof and tension applying means for applying a tension in the lengthwise direction of the linear guide rail to the band-like cover body, wherein the tension applying means includes a tension applying block arranged at the end of the linear guide rail, a plurality of pressing plates for pressing the band-like cover body on the upper face of the tension applying block, and a pressing plate fixing bolt for fixing the pressing plates on the upper face of the tension applying block; and a pair of right and left arm portions are provided on the tension applying block, and an engagement convex portion which engages with the concave portion is provided on the opposed inside faces of the arm portions.
Also, a second aspect of the present invention provides a dustproof device for linear guide rail, including a band-like cover body covering a guide rail face including bolt holes for bolting a linear guide rail and tension applying means for applying a tension in the lengthwise direction of the linear guide rail to the band-like cover body, wherein the tension applying means includes a tension applying block arranged at the end of the linear guide rail, a plurality of pressing plates for pressing the band-like cover body on the upper face of the tension applying block, and a pressing plate fixing bolt for fixing the pressing plates on the upper face of the tension applying block; and a pair of right and left arm portions which press the linear guide rail from both sides are provided on the tension applying block.
Also, a third aspect of the present invention provides a dustproof device for linear guide rail, including a band-like cover body covering a guide rail face including bolt holes for bolting a linear guide rail on a rail attachment surface and tension applying means for applying a tension in the lengthwise direction of the linear guide rail to the band-like cover body, wherein the tension applying means includes a tension applying member arranged at the end of the linear guide rail, a plurality of pressing plates for pressing the band-like cover body on the tension applying member, a pressing plate fixing bolt for fixing the pressing plates on the tension applying member, and a plurality of tension applying member fixing bolts for fixing the tension applying member on the rail attachment surface.
In the dustproof device for linear guide rail in accordance of the first aspect of the present invention, when the engagement convex portion of the arm portion provided on the tension applying block engages with the concave portion such as a rolling element rolling groove in the linear guide rail, the tension applying block becomes in a state in which the vertical movement thereof is restrained. Thereby, even if the tension applying block is not fixed to the end face of the linear guide rail by bolts, a tension can be applied to the band-like cover body. Therefore, the bolt holes in the linear guide rail can be protected from foreign matters such as cutting dust without many tap holes formed in the end face of the linear guide rail.
It is preferable that the tension applying block have an upper step portion adjoining the linear guide rail and a lower step portion formed continuously with the rear end of the upper step portion, and the pressing plates be fixed on the upper face of the lower step portion in a state of being laminated. By this configuration, the slack of the band-like cover body can be adjusted and absorbed by utilizing a riser formed between the upper step portion and the lower step portion of the tension applying block. Also, a face on which the pressing plates of the tension applying block is fixed is preferably lower than a face with which the band-like cover body of the linear guide rail comes into contact.
Also, the tension applying block preferably has a concave positioning portion for positioning the band-like cover body in the center on the upper face of the tension applying block. By this configuration, the guide rail face including bolt holes can surely be covered by the band-like cover body.
Further, it is preferable that the pressing plate have a through hole for causing a threaded portion of the pressing plate fixing bolt to pass through, and the through hole be formed into an elongated shape along the lengthwise direction of the band-like cover body.
In the second aspect of the present invention, the tension applying member is made in a state in which the vertical movement thereof is restrained by the paired arm portions provided on the tension applying member, and a tension can be applied to the band-like cover body even if the tension applying block is not fixed to the end face of the linear guide rail by bolts. Therefore, the bolt holes in the linear guide rail can be protected from foreign matters such as cutting dust without many tap holes formed in the end face of the linear guide rail.
In the third aspect of the present invention, the tension applying member is made in a state in which the vertical movement thereof is restrained by the tension applying member fixed on the rail attachment surface by the tension applying member fixing bolts, and a tension can be applied to the band-like cover body even if the tension applying member is not fixed to the end face of the linear guide rail by bolts. Therefore, the bolt holes in the linear guide rail can be protected from foreign matters such as cutting dust without many tap holes formed in the end face of the linear guide rail.